This invention relates generally to a pull type swather or windrower and, more particularly, to a pull type swather which features a double swath capability and enhanced transport to operation mode conversion characteristics.
As the size of wheat farms increases, it is desirable to reduce the amount of operator time in the field by enlarging operating machinery. In cutting a crop with a swather or windrower, it is clearly desirable to cut as much crop as possible with one pass of the swather so that time of operator and equipment in the field can be reduced. Thus, the size of swathers has increased over the last few years from ten and twenty to forty feet in width and even wider.
While the increased width of swathers serves the function of decreasing field time well, the size of large swathers has unattractive features. For example, the large size of such swathers in operation causes transportation problems as often the crop in the field is far removed from the location where the equipment is generally stored and it may be necessary to transport the swather along public roads and through openings designed for smaller vehicles. While a transport mode has been designed for many large swathers, such a mode requires various relatively large changes to the swather such as adding stabilizer wheels, wheel spindles, hitches and the like to avoid an unstable apparatus while the swather is under transport. This is undesirable from an efficiency and a cost viewpoint.
Yet a further undesirable feature of most large pull type swathers is that only one swath, separated from another swath by a relatively large distance, can be obtained. If a second swath is located adjacent a first swath, the tractor may have to travel through the first swath which is obviously unacceptable. Two adjacent swaths are desirable in order to reduce the operating time of a combine which will subsequently gather and thresh the swath. While double swath capabilities on pull type swathers have been obtained, these are usually obtained only by extending the draper deck. Such an addition is expensive and bulky and the complexity of the addition often may result in failure of the addition in the field as well as poor swath formation.
Yet a further undesirable feature of present large swathers is that as ground speeds increase and in travelling over rough terrain, the typical sidewise extending operating position is difficult to maintain in its correct operating position because the moment created by the heavy weight of the swather will tend to create an angle between the swather and a line normal to the pulling tractor. Such an angle causes cutting dislocations and inconsistent swaths. To overcome this problem, an approach used has been to lighten the machine which can result in the deletion of attractive features such as table flotation, table lift characteristics and the like. This is clearly unsatisfactory.
Yet a further problem with pull type swathers relates to the flexibility of laying the swath. With present pull type swathers, there is no ability to lay a swath in the centre portion of the swather and, as well, to also lay the swath at either end of the table.